The detective in charge of the criminal investigation into Jeremy Vine’s stalker has been given “substantial” compensation after being libelled and accused of being part of a “witch hunt” with the BBC.

Alex Belfield, a former BBC local radio presenter, was jailed for five years and 26 weeks in September 2022 after being convicted of four stalking charges against broadcasters, including the Channel 5 and BBC Radio 2 presenter.

Belfield, then aged 42, was found guilty after a trial at Nottingham Crown Court of waging a relentless stalking campaign, with Mr Vine subjected to an “avalanche of hatred”.

On Thursday, the High Court heard that Belfield had published 15 videos referring to the officer in charge of the criminal investigation into his stalking, Detective Constable Janet Percival.

Jeremy Clarke-Williams, for Ms Percival, told the court in London the videos made several allegations, including describing the officer as corrupt, alleging she had lied in court, and claiming she “had colluded with the BBC in a witch hunt against the defendant as part of an unlawful conspiracy to destroy him”.

The solicitor said: “These allegations were not only untrue, they were without any foundation.

“Janet Percival had conducted herself entirely professionally and properly as a police officer, and in her investigations in the criminal case against the defendant, just as she always has done in her police work.”

Ms Percival brought a libel claim against Belfield, with the former radio presenter accepting liability, retracting the false allegations and paying a “substantial sum” in compensation as well as her legal costs.

Mr Clarke-Williams continued: “Considerable harm was caused to the personal reputation of Janet Percival, not just within the community where she lives and works, and where her reputation is most important, but also to a much wider audience.

“As a serving police officer, the claimant is, unfortunately, used to dealing with hostility from people she has arrested, but the defendant’s online campaign peddling serious untruths about her was something she could not ignore. It was too damaging.”

Alan Robertshaw, for Belfield, said: “Alex Belfield offers his sincere and unqualified apology to Janet Percival for the embarrassment and distress caused to her and for the serious harm to her professional and personal reputation.”

Mr Robertshaw added at the hearing before Mr Justice Nicklin that the apology will be published on Belfield’s social media accounts.

The apology comes after Belfield settled a civil claim brought against him by Mr Vine, related to “entirely false” allegations in nine YouTube videos and eight tweets put online between May and August 2020.

Mr Vine previously labelled Belfield “the Jimmy Savile of trolling” during the criminal trial, which heard that he repeatedly posted or sent abusive messages, videos and emails.

Jurors accepted Belfield caused serious alarm or distress to two victims and found him guilty of “simple” stalking in relation to Mr Vine and theatre blogger Philip Dehany.